Boiler feed system



Patented Aug. 26, 1952 srr BOELER FEED SYSTEM Eugene J. Le Claire andBernard J. Heinzinan, St. Paul, Minn., assignors to Harry Ii. J costing,

St. Paul, Minn.

11 Claims.

Our invention relates to an improvement in boiler feed systems whereinit is desired to employ a relatively low water pressure to feed a boileroperating at substantiallyhigher pressure.

In the feeding of boilers it is usual practice to I provide some meansof building up suficient pressure behind the feed water to force thefeed water into the boiler. There are two common means of building upthis pressure. A boiler water feed pump is sometimes provided to producethe necessary water pressure. In other instances an injector is employedto force the water into the boiler under pressure. Both of these meansare costly to operate and maintain in proper operation.

It is the object of thepresent invention to provide a means of using arelatively low pressure water supply to feed a relatively high pressureboiler. This we accomplish by feeding low pressure water into a supplytank, equalizing pressure on both sides of said tank, and allowing thewater to feed into the boiler by gravity. As 'a result the water willfeed properly into the boiler regardless of the fact that the feed wateris supplied at extremely low pressure.

A feature of the present invention resides in the fact that our feedwater'system is entirely automatic. As soon as the level of Water in thesupply tank drops below a desired level more Water is fed thereinto.When suiiicient water is in the supply tank the water supply isautomatically cut oil and the pressure on opposite sides of the supplytank equalized, allowin the water to feed by gravity into the boiler. r

A further feature of the present invention resides in the factthat thereare no manualcontrols which must be actuated to supply water to theboiler. The steam connections remain constantly connected to the watersupply tank to avoid the necessity of cutting off the steam supply inorder to reduce the pressure in the supply tank.

A further feature of the present invention resides in the fact that thesteam pressure above the water in the water supply tank is reduced byopening a vent therein to permit the pressure to drop below the pressureof the water supply. By opening a passage between the pressure tank andthe atmosphere, the top of the water supply tank may be reduced toatmospheric pressure, allowing water to enter the tank under anypressure in excess of atmospheric pressure.

A further feature of the present invention resides in the use of a noveltype of Weight for assisting the float operation of the venting valve inthe Water supply tank. A float holds this venti valve closed when theWater in the tank is at the proper level and the weight of the float andvalve tends'to open the valve when the water level in the supply tankdrops. In order to assist the weight of the float and valve in openingthe valve ,a water container having an opening in the top thereof issupported on the valve mechanism. Whenthis container is submerged inwater there is little weight exerted upon the valve. However. when thelevel of water outwardly'of the container falls, the weight ofwaterwithin the container is added to the weight of the container Theseand other objects and novel features of our invention will be moreclearly and'fully set forth in the following specification and claims.

In'thedrawings forming a part of our specification:

Figure 1 is a'dia-grammatic view of our water supply tank, boiler andfloat valve regulating the level of water within the boiler. I

Figure 2 is a vertical section through the water supply tank showing theconstruction thereof.

Figure 3 isa sectional view through thewater supply tank .nearthe bottomthereof.

As best indicated in Figure 1 of the drawings the boiler A is suppliedwith water from a water supply tank B. A float valve C is provided inthe water supply line from the tank to the boiler to regulate the waterlevel within the boiler.

The boiler A is provided with a steam outlet it which may provide steamto any'desired apparatus. A pipe line H leads to a check valve 12. Thecheck valve 52 permits steam to pass through the pipe line H in adirection away from the boiler A toward the water supply tank B, butprevents a reverse flow of steam or water. The check valve [2 isconnected by the pipe line 13 to the T I l. The opposite end of the T Mis connected to the inlet tube or connection [5.

The water supply line it is connected to the T M and includes a checkvalve [7. The check valve ll permits a flow of water into the watersupply tank B, but prevents the flow of water or steam rearwardly intothe water supply line. The

water supply tank B is connetced to the feed line I9 leading to thefloat valve C. The top of the float valve is connected by the connectionto the top of the boiler A, thus communicating steam pressure to the topof the float valve. The bottom of the float valve C is connected by theboiler feed line 2I to the boiler A.

It will be seen that the top and bottom of the float valve C issubjected to the same pressure. Thus in the event the water level in theboiler A should drop somewhat, water may feed thereinto by gravity.

The water supply tank B is best illustrated in Figure 2 of the drawings.The tank B is shown as having side walls 22, a bottom closure 23 and atop closure 24. One end of the tank B is preferably removably securedand in Figure 2 the tank end 24 is shown connected to the flange 25 onthe tank side walls 22 by means of bolts 26.

A bushing or nipple 21 having a central aperture 28 therethrough issecured extending through the top closure plate 24. The lower end ofthis bushing or nipple 21 is provided with a tapered valve seat 30 whichmay be engaged by the tapering end 3I of the vent valve rod 32. Thevalve rod 32 is slidably supported by a guiding frame 33 secureddepending from the top closure plate 24 and at its lower end issupported by a guide disc 34. The rod or stem 32 extends centrallythrough the disc 34 and angularly spaced apertures 35 are provided inthis disc to permit the free flow of liquid therethrough into the upperextremity 36 of the feed line I9.

A float 31 is secured to the valve rod 32 to actuate the same. The float31 is shown comprising a hollow spherical shell 39 having a central tube40 extending therethrough. The valve rod 32 extends through the tube 40.Shoulders or projections H and 42 on the rod 32 hold the float 31 fromsliding relative to the valve rod 32.

Secured to the valve rod 32 above the level of the float 31 we provide acontainer 43 which is secured to the valve rod for movement therewith.The container 43 is shown as having cylindrical side walls 44 and aconvex bottom 45. A flat top 46 having an opening 41 therethrough closesthe major portion of the top of the container 43. The inlet tube I5extends into this opening 47, thereby preventing the rotation of thecontainer 43 and valve rod 32. Perforations 49 are provided through theinlet tube I5 above the level of the container 43 and the bottom end ofthe tube I5 is closed as indicated at 50.

In operation the boiler is filled to the desired level by the floatvalve C, this float valve C receiving liquid through the feed connectionI 9 from the supply tank B. The supply tank B is fed from the watersupply line I6. Before the boiler has been started no steam has beendeveloped and there is no pressure in the steam lines II and I3, thuspermitting fluid to flow freely into the supply tank B.

The boiler is now started into operation and steam under pressure flowsthrough the pipe lines II and I3 as well as the check valve I2, thusproviding a pressure above the liquid in the tank B. Steam pressure isalso equalized within the float valve C, permitting water to flow fromthe float valve into the boiler. The water supplied to the float valve Cis drawn through the feed line I9 from the tank B. Thus gradually thelevel of liquid in the tank B drops.

When the tank'B is nearly full of water the container 43 is submerged sothat only the weight of the tank itself exerts a downward pressure uponthe valve rod 32. Even the weight of the tank 43 is partially overcomeby the surrounding water. However, as the level of water in the tank Bdrops, less and less of the container 43 remains submerged. If thecontainer 43 remains full of water the efiective weight acting upon therod 32 greatly increases until this downward force is suflicient tolower the valve rod 32.

As the valve rod 32 moves into the open position shown in full lines inFigure 2 of the drawings the steam pressure within the top of the tank Bis vented to atmosphere, thereby quickly dropping the pressure withinthe top of the tank B. If as an example the steam pressure in the top ofthe tank B is initially seventy pounds and if the city water pressure isfed to the tank at thirty-five pounds pressure, as soon as the P surewithin the top of the tank B drops below thirty-five pounds the checkvalve I! will open and water will feed through the inlet I 5 and intothe interior of the tank B.

When the vent valve 21 opens steam also passes through the lines II andI3 and through the check valve I2. However, the steam pressure withinthe top of the tank drops faster than the entering steam can build itup, due to the restriction 5I in the steam line I3, thus allowing waterto enter through the supply line I6. When the steam passing through thelines I I and I3 strikes the water entering through the water supplyline IS, the steam is condensed, thereby losing its pressure. v

Water continues to feed through the inlet tube I5 until the float 31again raises the valve rod 32 to close the vent valve. This closure ofthe vent valve will not take place until the container 43 is at leastpartially submerged in liquid thus lowering the effective weight of thecontainer 43.

As soon as the vent valve is closed the entering steam again brings upsuflicient pressure to close the check valve I! and to equalize pressureon opposite sides of the supply liquid. Thereupon liquid may drain fromthe tank B into the fluid chamber as required.

It will be seen that a relatively low water pressure may thusautomatically feed into a boiler operating at considerably higherpressure. If the fluid and check valves are sturdy, there is little ornothing to go out of operation in the device described. The taperingvalve 3| can not easily clog up due to the fact that each time thisvalve opens steam under pressure passes through the vent aperture 29. Wehave found our boiler feed apparatus extremely reliable, simple inconstruction, and entirely automatic in operation. Furthermore, we havefound that the small amount of steam entering the water supply tankheats the tank considerably, thereby permitting water to be fed to theboiler in a preheated condition.

In accordance with the patent statutes, we have described the principlesof construction and operation of our boiler feed systems, and while wehave endeavored to set forth the best embodiment thereof, we desire tohave it understood that obvious changes may be made within the scope ofthe following claims without departin from the spirit of our invention.

We claim:

1. A liquid feed apparatus comprising a closed chamber, a dischargepassage therefrom including means for at times blocking dischargetherethrough, an inlet thereto, a relatively high pressure steam lineconnected to said inlet, means for limiting the flow of steam throughsaid steam line, a liquid supply line to said chamber, check valve insaid liquid supply line to prevent a reverse flow away from saidchamber, the pressure of said liquid supply line being smaller than thepressure of steam in said steam line, a vent, opening in said chamber oflarger cross-sectional area than saidsteam flow limiting means, andmeans for controlling the opening and closing of said vent opening, saidvent opening when open acting to reduce the pressure in said chamberbelow the pressure of liquid in said liquid feed line to permit liquidto flow into said chamber.

2. A liquid feed apparatuscomprising a closed chamber, a dischargepassage therefrom including means for at times blocking dischargetherethrough, and a relatively high pressure steam line continuouslyconnected to said chamber above the liquid level therein, a relativelylower pressure liquid feed line connected to said chamber, a check valvein said liquid feed line to prevent the flow of fluid away from saidchamber, a restriction in said steam line to restrict the steam flow tothe chamber, vent means for connecting said chamber to atmosphere, saidvent means being of larger cross-sectional area than said restriction,and means controlling the opening and closing of said vent means,lowering of pressure in said chamber allowing liquid to enter from saidliquid feed line.

3. A liquid feed apparatus comprising a closed chamber, a dischargepassage therefrom including means for at times blocking dischargetherethrough, an inlet thereto, a relatively high pressure gas pressureline connected to said inlet, means for limiting the flow of gaspressure through said gas pressure line, a liquid supply line to saidchamber, check valve in said liquid supply line to prevent a reverseflow away from said chamber, the pressure of said liquid supply linebeing smaller than the pressure of gas pressure in said gas pressureline, a vent opening in said chamber, said vent opening being largerelative to said flow limiting means, and said vent permitting a greaterflow of gas than the gas flow limiting means, and means for controllingthe opening and closing of said vent opening, said vent opening whenopen acting to reduce the pressure in said chamber below the pressure ofliquid in said liquid feed line to permit liquid to flow into saidchamber, said vent opening allowing pressure in said chamber to dropfaster than said gas pressure line can supply pressure.

4. A pressure feed device comprising a closed float chamber, conduitmeans leading from said chamber to discharge liquid therefrom into apressure region including means for at times blocking discharge throughsaid discharge conduit, gas pressure supply conduit means extendin intosaid chamber above the surface of the liquid therein for equalizing thepressure in the chamber with the pressure in said region, a liquid feedline extending into said conduit means for supplying liquid at apressure below the gas pressure in said conduit means, check meansrespectively in said conduit means and said liquid line to prevent flowof fluid away from said chamber through said conduit means and feedline, vent means above the liquid level in said chamber, said vent meanshaving a greater effective crosssectional area than said conduit meansto thereby lower the pressure in said chamber below that of the waterfeed line upon opening or the vent means, and float actuated valve meansfor closing said vent means.

5. A pressure feed apparatus comprising a closed float chamber, apressure discharge line means leading therefrom into a pressure regionincluding means for at times blocking discharge through said dischargeline, an inlet extending thereinto above the liquid level therein, asteam pressure line connected to said inlet for equalizing the pressurein said chamber with the pressure in said regiomfa 'liquidfeed lineconnected to said inlet supplying water at a pressure below normal steampressure in said steam line, check valves respectively in said steamline and said liquid feed line to prevent the flow'of fluid away fromsaid chamber, avent in said chamber above liquid level, said vent havingra larger effective cross sectional area than said steam line, and floatactuated means for closing said vent opening. f H i 6. A pressure feedapparatus comprising a closed float chamber, a discharge passage meanstherefrom leading into a pr'essure'region including means for at timesblocking discharge through said discharge passage, an inlet theretoabove liquid level, a relatively high steam pressure line and'arelatively lower water pressure line connected to said inlet, a checkvalve insaid water line to-pr'event a reverse flow away from saidchamber, a vent opening above liquid level in said chamber, said venthaving a relatively greater effective cross-sectional area than saidsteam line, and a float actuated valve for closing said vent opening.

7. A liquid feed device comprising a closed float chamber, a dischargepassage means ex tending therefrom into a pressure region includingmeans for at times blocking discharge through said discharge passage, aninlet passage extending thereto, a relatively high pressure steam lineand a relatively lower pressure liquid feed line connected to saidinlet, a check valve in said liquid feed line to prevent the flow offluid away from said chamber, a vent valve above liquid level in saidchamber, said vent having a relatively greater effective cross-sectionalarea than said steam line, and float actuated valve means for closingsaidvent opening.

8. A pressure feed device comprising a closed float chamber, a dischargepassage means there from leading into a pressure region including meansfor atv times blocking discharge through said discharge passage, aninlet passage thereto above liquid level, a T connection on said inlet,a relatively high pressure steam line connected to one outlet of said Tconnection, a relatively lower pressure liquid feed line connected tothe other T outlet, a check valve in said liquid feed line to preventthe flow of fluid away from said chamber, and means for relievingpressure within said chamber comprising a vent opening in said chamber,said vent having a relatively greater efiective cross-sectional areathan said steam line, and a float valve for closing said vent opening.

9. A pressure feed apparatus comprising a closed pressure chamber, apressure discharge passage means therefrom including means to at timesblock flow therethrough, an inlet thereto, relatively high pressuresteam and relatively lower pressure liquid lines connected to saidinlet, a

steam line soas to destroy the pressure effect thereof.

10. A pressure feed apparatus comprising a closed feed chamber, apressure discharge means therefrom including means to at times blockflow therethrough, an inlet thereto above the liquid level, a relativelyhigh pressure steam line and a relatively low pressure water lineconnected to said inlet, a check valve in said liquid supply line toprevent liquid from flowing away from said chamber, a vent valve in saidchamber, and means for closing said vent valve, said vent valve being oflarger eifective cross-sectional area than the steam pressure line tothereby be capable of lowering the pressure in said pressure chamberbelow the pressure of the liquid supply when the vent is open, therebyallowing liquid to enter said chamber, the liquid acting to condense thesteam and to substantially destroy the pressure thereof.

11. A liquid feed apparatus comprising a closed pressure chamber, adischarge means therefrom including means at times to block flowtherethrough, an inlet thereto, a relatively high pressure steam lineand a relatively lower pressure liquid feed line connected to saidinlet, a check valve in said liquid feed line to prevent the flow offluid in a reverse direction away from said chamber, means for at timeslowering the pressure in said chamber, and means for restricting theflow of steam through said steam line, said pressure restricting meanscooperating with said pressure lowering means to reduce pressure fasterthan said steam feed line may build pressure up so as to drop thepressure in said chamber sufficiently to permit said liquid feed line todeliver liquid to said chamber.

EUGENE J. LE CLAIRE. BERNARD J. HEINZMAN.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 1,252,967 'I'rane Jan. 8, 19181,362,150 Shealy Dec. 14, 1920 1,672,610 Goff June 5, 1928

